Studying Renal Artery Bifurcation Structure in Male Dogs

Introduction: Arteries are made up three layers; tunica intima, tunica media, and tunica adventitia. However, in some part of the artery this structure may change. The greatest change occurs at the junctions and bifurcations. In this regard, we decided to study the renal artery bifurcation just where the renal arteries divide into smaller arteries before entering the kidney. Methods: The structure of renal artery bifurcation was assessed in six normal male dogs by light microscopy. Also the thickness of the tunica intima, tunica media, and tunica adventitia before and after bifurcation area was measured.  Results: Tunica intima cannot be seen in this area and tunica media in one side and tunica adventitia in other side were very thick. It seems that division of renal artery happens with the penetration of tunica adventitia in one side and tunica media in the other side. Conclusion: In this area, the artery has thick tunica media on one side and thick tunica adventitia on the other side and these differences were significant. The circular and longitudinal smooth muscle cells can be seen in renal artery bifurcation. These structures may be due to function of this area to maintain and control blood pressure and prevent artery from bursting and dilation.